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<H1 class="no-header">curs_util 3x 2025-02-15 ncurses 6.5 Library calls</H1>
<PRE>
<STRONG><A HREF="curs_util.3x.html">curs_util(3x)</A></STRONG>                    Library calls                   <STRONG><A HREF="curs_util.3x.html">curs_util(3x)</A></STRONG>




</PRE><H2><a name="h2-NAME">NAME</a></H2><PRE>
       <STRONG>delay_output</STRONG>,  <STRONG>filter</STRONG>,  <STRONG>flushinp</STRONG>,  <STRONG>getwin</STRONG>, <STRONG>key_name</STRONG>, <STRONG>keyname</STRONG>, <STRONG>nofilter</STRONG>,
       <STRONG>putwin</STRONG>, <STRONG>unctrl</STRONG>, <STRONG>use_env</STRONG>, <STRONG>use_tioctl</STRONG>,  <STRONG>wunctrl</STRONG>  -  miscellaneous  <EM>curses</EM>
       utility routines


</PRE><H2><a name="h2-SYNOPSIS">SYNOPSIS</a></H2><PRE>
       <STRONG>#include</STRONG> <STRONG>&lt;curses.h&gt;</STRONG>

       <STRONG>const</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG> <STRONG>unctrl(chtype</STRONG> <EM>ch</EM><STRONG>);</STRONG>
       <STRONG>wchar_t</STRONG> <STRONG>*</STRONG> <STRONG>wunctrl(cchar_t</STRONG> <STRONG>*</STRONG> <EM>wch</EM><STRONG>);</STRONG>

       <STRONG>const</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG> <STRONG>keyname(int</STRONG> <EM>c</EM><STRONG>);</STRONG>
       <STRONG>const</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG> <STRONG>key_name(wchar_t</STRONG> <EM>wc</EM><STRONG>);</STRONG>

       <STRONG>void</STRONG> <STRONG>filter(void);</STRONG>
       <EM>/*</EM> <EM>extension</EM> <EM>*/</EM>
       <STRONG>void</STRONG> <STRONG>nofilter(void);</STRONG>

       <STRONG>void</STRONG> <STRONG>use_env(bool</STRONG> <EM>bf</EM><STRONG>);</STRONG>
       <EM>/*</EM> <EM>extension</EM> <EM>*/</EM>
       <STRONG>void</STRONG> <STRONG>use_tioctl(bool</STRONG> <EM>bf</EM><STRONG>);</STRONG>

       <STRONG>int</STRONG> <STRONG>putwin(WINDOW</STRONG> <STRONG>*</STRONG> <EM>win</EM><STRONG>,</STRONG> <STRONG>FILE</STRONG> <STRONG>*</STRONG> <EM>filep</EM><STRONG>);</STRONG>
       <STRONG>WINDOW</STRONG> <STRONG>*</STRONG> <STRONG>getwin(FILE</STRONG> <STRONG>*</STRONG> <EM>filep</EM><STRONG>);</STRONG>

       <STRONG>int</STRONG> <STRONG>delay_output(int</STRONG> <EM>ms</EM><STRONG>);</STRONG>

       <STRONG>int</STRONG> <STRONG>flushinp(void);</STRONG>


</PRE><H2><a name="h2-DESCRIPTION">DESCRIPTION</a></H2><PRE>

</PRE><H3><a name="h3-unctrl_wunctrl">unctrl, wunctrl</a></H3><PRE>
       <STRONG>unctrl</STRONG>   returns   a   null-terminated   character   string   printably
       representing the <EM>curses</EM> character <EM>ch</EM>,  often  one  that  originated  in
       keyboard input; see <STRONG><A HREF="curs_getch.3x.html">getch(3x)</A></STRONG>.

       <STRONG>o</STRONG>   Printable   characters  represent  themselves  as  a  one-character
           string.

       <STRONG>o</STRONG>   Control characters are expressed in <STRONG>^</STRONG><EM>X</EM> notation,  where  <EM>X</EM>  is  the
           printable  symbol  of  the  control  code's  value  plus  32 in the
           ISO 646/"ASCII" character set.

       <STRONG>o</STRONG>   DEL (character code 127) is represented as <STRONG>^?</STRONG>.

       <STRONG>o</STRONG>   A character code greater than 127 is  represented  in  one  of  two
           ways.

           If  the  screen  has  not  been initialized or is in meta mode (see
           <STRONG><A HREF="curs_inopts.3x.html">meta(3x)</A></STRONG>), it  is  expressed  in  <STRONG>M-</STRONG><EM>X</EM>  notation,  where  X  is  the
           representation of the code's value minus 128, as described above.

           If the screen is not in meta mode, the character code is assumed to
           represent itself.  It nevertheless may not be  printable;  this  is
           the case for character codes 128-159 in ISO 8859 encodings.

           <EM>ncurses</EM>'s   <STRONG><A HREF="legacy_coding.3x.html">use_legacy_coding(3x)</A></STRONG>   function   configures  <STRONG>unctrl</STRONG>'s
           handling of these character codes.

       <STRONG>wunctrl</STRONG>  returns  a  null-terminated  wide-character  string  printably
       representing the <EM>curses</EM> complex character <EM>wch</EM>.

       Both  functions ignore the attributes and color pair selection of their
       argument.


</PRE><H3><a name="h3-keyname_key_name">keyname, key_name</a></H3><PRE>
       The <STRONG>keyname</STRONG> routine returns a character string corresponding to the key
       <EM>c</EM>.  Key codes are different from character codes.

       <STRONG>o</STRONG>   Key  codes  below  256  are  characters.   They are displayed using
           <STRONG>unctrl</STRONG>.

       <STRONG>o</STRONG>   Values above 256 may be the codes for function keys.  The  function
           key name is displayed.

       <STRONG>o</STRONG>   Otherwise  (if  there is no corresponding name and the key is not a
           character) the function returns null, to denote an  error.   X/Open
           also   lists   an   "UNKNOWN   KEY"   return   value,   which  some
           implementations return rather than null.

       The  corresponding  <STRONG>key_name</STRONG>  returns  a  multibyte  character   string
       corresponding  to  the  wide-character  value  <EM>wc</EM>.   The  two functions
       (<STRONG>keyname</STRONG> and <STRONG>key_name</STRONG>) do not return the same set of strings:

       <STRONG>o</STRONG>   <STRONG>keyname</STRONG> returns null where <STRONG>key_name</STRONG> would display a meta character.

       <STRONG>o</STRONG>   <STRONG>key_name</STRONG> does not return the name of a function key.


</PRE><H3><a name="h3-filter_nofilter">filter, nofilter</a></H3><PRE>
       The <STRONG>filter</STRONG> routine, if used, must be called before <STRONG>initscr</STRONG>  or  <STRONG>newterm</STRONG>
       are called.  Calling <STRONG>filter</STRONG> causes these changes in initialization:

       <STRONG>o</STRONG>   <STRONG>LINES</STRONG> is set to 1;

       <STRONG>o</STRONG>   the  capabilities  <STRONG>clear</STRONG>,  <STRONG>cud1</STRONG>,  <STRONG>cud</STRONG>,  <STRONG>cup</STRONG>,  <STRONG>cuu1</STRONG>,  <STRONG>cuu</STRONG>,  <STRONG>vpa</STRONG>  are
           disabled;

       <STRONG>o</STRONG>   the capability <STRONG>ed</STRONG> is disabled if <STRONG>bce</STRONG> is set;

       <STRONG>o</STRONG>   and the <STRONG>home</STRONG> string is set to the value of <STRONG>cr</STRONG>.

       The <STRONG>nofilter</STRONG> routine cancels the effect of  a  preceding  <STRONG>filter</STRONG>  call.
       That  allows  the  caller to initialize a screen on a different device,
       using a different value of <STRONG>$TERM</STRONG>.  The limitation  arises  because  the
       <STRONG>filter</STRONG> routine modifies the in-memory copy of the terminal information.


</PRE><H3><a name="h3-use_env">use_env</a></H3><PRE>
       The  <STRONG>use_env</STRONG>  routine,  if  used,  should  be  called before <STRONG>initscr</STRONG> or
       <STRONG>newterm</STRONG> are  called  (because  those  compute  the  screen  size).   It
       modifies  the way <EM>ncurses</EM> treats environment variables when determining
       the screen size.

       <STRONG>o</STRONG>   Normally <EM>ncurses</EM> looks first  at  the  terminal  database  for  the
           screen size.

           If  <STRONG>use_env</STRONG>  was  called  with  <STRONG>FALSE</STRONG>  for parameter, it stops here
           unless <STRONG>use_tioctl</STRONG> was also called with <STRONG>TRUE</STRONG> for parameter.

       <STRONG>o</STRONG>   Then it asks for the screen size via operating  system  calls.   If
           successful, it overrides the values from the terminal database.

       <STRONG>o</STRONG>   Finally  (unless  <STRONG>use_env</STRONG> was called with <STRONG>FALSE</STRONG> parameter), <EM>ncurses</EM>
           examines the <EM>LINES</EM> or <EM>COLUMNS</EM> environment variables, using a  value
           in  those  to  override  the  results  from the operating system or
           terminal database.

           <EM>curses</EM> also updates the screen size in response to <STRONG>SIGWINCH</STRONG>, unless
           overridden by the <EM>LINES</EM> or <EM>COLUMNS</EM> environment variables,


</PRE><H3><a name="h3-use_tioctl">use_tioctl</a></H3><PRE>
       The  <STRONG>use_tioctl</STRONG>  routine,  if  used, should be called before <STRONG>initscr</STRONG> or
       <STRONG>newterm</STRONG> are called (because those  compute  the  screen  size).   After
       <STRONG>use_tioctl</STRONG>  is  called  with  <STRONG>TRUE</STRONG> as an argument, <EM>ncurses</EM> modifies the
       last step in its computation of screen size as follows:

       <STRONG>o</STRONG>   checks whether the <EM>LINES</EM> and <EM>COLUMNS</EM> environment variables are  set
           to a number greater than zero.

       <STRONG>o</STRONG>   for  each,  <EM>ncurses</EM>  updates the corresponding environment variable
           with the value that it has obtained via operating  system  call  or
           from the terminal database.

       <STRONG>o</STRONG>   <EM>ncurses</EM>  re-fetches  the value of the environment variables so that
           it is still the environment variables that set the screen size.

       The <STRONG>use_env</STRONG> and <STRONG>use_tioctl</STRONG> routines combine as follows.

              <STRONG>use_env</STRONG>   <STRONG>use_tioctl</STRONG>   <STRONG>Summary</STRONG>
              -----------------------------------------------------------------
              <STRONG>TRUE</STRONG>      <STRONG>FALSE</STRONG>        <EM>ncurses</EM>  uses  operating   system   calls
                                     unless  overridden  by  <EM>LINES</EM>  or <EM>COLUMNS</EM>
                                     environment variables; default.
              <STRONG>TRUE</STRONG>      <STRONG>TRUE</STRONG>         <EM>ncurses</EM> updates <EM>LINES</EM> and  <EM>COLUMNS</EM>  based
                                     on operating system calls.
              <STRONG>FALSE</STRONG>     <STRONG>TRUE</STRONG>         <EM>ncurses</EM>  ignores <EM>LINES</EM> and <EM>COLUMNS</EM>, using
                                     operating system calls to obtain size.


</PRE><H3><a name="h3-putwin_getwin">putwin, getwin</a></H3><PRE>
       The <STRONG>putwin</STRONG> routine writes all data associated with window (or pad)  <EM>win</EM>
       into  the  file  to  which <EM>filep</EM> points.  This information can be later
       retrieved using the <STRONG>getwin</STRONG> function.

       The <STRONG>getwin</STRONG> routine reads window related data  stored  in  the  file  by
       <STRONG>putwin</STRONG>.   The  routine  then creates and initializes a new window using
       that data.  It returns a pointer to the new window.  There  are  a  few
       caveats:

       <STRONG>o</STRONG>   the  data  written  is  a  copy  of  the  <EM>WINDOW</EM> structure, and its
           associated character cells.  The format differs between  the  wide-
           character  (<EM>ncursesw</EM>)  and  non-wide  (<EM>ncurses</EM>) libraries.  You can
           transfer data between the two, however.

       <STRONG>o</STRONG>   the retrieved window is always created as a  top-level  window  (or
           pad), rather than a subwindow.

       <STRONG>o</STRONG>   the  window's character cells contain the color pair <EM>value</EM>, but not
           the actual color <EM>numbers</EM>.  If cells in  the  retrieved  window  use
           color  pairs  that  have  not been created in the application using
           <STRONG>init_pair</STRONG>, they will not be colored when the window is refreshed.


</PRE><H3><a name="h3-delay_output">delay_output</a></H3><PRE>
       The <STRONG>delay_output</STRONG> routine inserts an <EM>ms</EM>  millisecond  pause  in  output.
       Employ  this  function  judiciously  when terminal output uses padding,
       because <EM>ncurses</EM>  transmits  null  characters  (consuming  CPU  and  I/O
       resources)  instead  of  sleeping  and  requesting  resumption from the
       operating system.  Padding is used unless:

       <STRONG>o</STRONG>   the terminal description has <STRONG>npc</STRONG> (<STRONG>no_pad_char</STRONG>) capability, or

       <STRONG>o</STRONG>   the environment variable <STRONG>NCURSES_NO_PADDING</STRONG> is set.

       If padding is not in use, <EM>ncurses</EM> uses <STRONG>napms</STRONG> to perform the delay.   If
       the  value  of <EM>ms</EM> exceeds 30,000 (thirty seconds), it is capped at that
       value.


</PRE><H3><a name="h3-flushinp">flushinp</a></H3><PRE>
       The <STRONG>flushinp</STRONG> routine throws away any typeahead that has been  typed  by
       the user and has not yet been read by the program.


</PRE><H2><a name="h2-RETURN-VALUE">RETURN VALUE</a></H2><PRE>
       Except  for  <STRONG>flushinp</STRONG>,  functions  that return integers return <STRONG>ERR</STRONG> upon
       failure and <STRONG>OK</STRONG> upon success.

       Functions that return pointers return <EM>NULL</EM> on error.

       In <EM>ncurses</EM>,

       <STRONG>o</STRONG>   <STRONG>flushinp</STRONG> returns <STRONG>ERR</STRONG> if the terminal was not initialized, and

       <STRONG>o</STRONG>   <STRONG>putwin</STRONG> returns <STRONG>ERR</STRONG> if its associated <STRONG>write(2)</STRONG> calls return <STRONG>ERR</STRONG>.


</PRE><H2><a name="h2-NOTES">NOTES</a></H2><PRE>
       <STRONG>wunctrl</STRONG> is part of <EM>ncurses</EM>'s wide-character API, and is  not  available
       in its non-wide configuration.


</PRE><H2><a name="h2-PORTABILITY">PORTABILITY</a></H2><PRE>
       X/Open Curses Issue 4 describes these functions.  It specifies no error
       conditions for them.

       SVr4 describes a successful return value  only  as  "an  integer  value
       other than <EM>ERR</EM>".


</PRE><H3><a name="h3-filter">filter</a></H3><PRE>
       The  SVr4  documentation  describes  the  action  of <STRONG>filter</STRONG> only in the
       vaguest terms.  The description here  is  adapted  from  X/Open  Curses
       (which erroneously fails to describe the disabling of <STRONG>cuu</STRONG>).


</PRE><H3><a name="h3-delay_output-padding">delay_output padding</a></H3><PRE>
       The  limitation  to  30  seconds and the use of <STRONG>napms</STRONG> differ from other
       implementations.

       <STRONG>o</STRONG>   SVr4 curses does not delay if no padding character is available.

       <STRONG>o</STRONG>   NetBSD curses uses <STRONG>napms</STRONG> when no padding  character  is  available,
           but  does  not  take  timing  into  account  when using the padding
           character.

       Neither limits the delay.


</PRE><H3><a name="h3-keyname">keyname</a></H3><PRE>
       The <STRONG>keyname</STRONG> function  may  return  the  names  of  user-defined  string
       capabilities  that  are defined in the terminfo entry via the <STRONG>-x</STRONG> option
       of <STRONG>tic</STRONG>.  This implementation  automatically  assigns  at  run-time  key
       codes to user-defined strings that begin with "k".  The key codes start
       at KEY_MAX, but are not guaranteed to be the same value  for  different
       runs   because   user-defined   codes  are  merged  from  all  terminal
       descriptions  that  have  been  loaded.    The   <STRONG><A HREF="curs_extend.3x.html">use_extended_names(3x)</A></STRONG>
       function  controls  whether  this  data  is  loaded  when  the terminal
       description is read by the library.


</PRE><H3><a name="h3-nofilter_use_tioctl">nofilter, use_tioctl</a></H3><PRE>
       The <STRONG>nofilter</STRONG> and <STRONG>use_tioctl</STRONG> routines are  specific  to  <EM>ncurses</EM>.   They
       were  not  supported on Version 7, BSD or System V implementations.  It
       is recommended  that  any  code  depending  on  <EM>ncurses</EM>  extensions  be
       conditioned using <STRONG>NCURSES_VERSION</STRONG>.


</PRE><H3><a name="h3-putwin_getwin-file-format">putwin/getwin file-format</a></H3><PRE>
       The <STRONG>putwin</STRONG> and <STRONG>getwin</STRONG> functions have several issues with portability:

       <STRONG>o</STRONG>   The   files   written   and   read   by   these  functions  use  an
           implementation-specific format.  Although the format is an  obvious
           target for standardization, it has been overlooked.

           Interestingly  enough,  according to the copyright dates in Solaris
           source, the functions (along with <STRONG>scr_init</STRONG>, etc.)  originated  with
           the University of California, Berkeley (in 1982) and were later (in
           1988) incorporated into SVr4.  Oddly, there are no  such  functions
           in the 4.3BSD curses sources.

       <STRONG>o</STRONG>   Most implementations simply dump the binary <EM>WINDOW</EM> structure to the
           file.  These include SVr4 <EM>curses</EM>, NetBSD <EM>curses</EM>, and  <EM>PDCurses</EM>,  as
           well  as  older  <EM>ncurses</EM> versions.  This implementation (as well as
           the X/Open variant of Solaris  curses,  dated  1995)  uses  textual
           dumps.

           The  implementations  that use binary dumps use block-I/O (<STRONG>write(2)</STRONG>
           and <STRONG>read(2)</STRONG> functions).  Those that use textual dumps use buffered-
           I/O.  A few applications may happen to write extra data in the file
           using these functions.  Doing that can  run  into  problems  mixing
           block-  and  buffered-I/O.  This implementation reduces the problem
           on writes by flushing the output.  However,  reading  from  a  file
           written using mixed schemes may not be successful.


</PRE><H3><a name="h3-unctrl_wunctrl">unctrl, wunctrl</a></H3><PRE>
       X/Open Curses Issue 4 describes these functions.  It specifies no error
       conditions for them.  It states that <STRONG>unctrl</STRONG> and <STRONG>wunctrl</STRONG> will  return  a
       null  pointer  if  unsuccessful.   This implementation checks for three
       cases:

       <STRONG>o</STRONG>   the parameter is a 7-bit US-ASCII code.   This  is  the  case  that
           X/Open Curses documented.

       <STRONG>o</STRONG>   the parameter is in the range 128-159, i.e., a C1 control code.  If
           <STRONG><A HREF="legacy_coding.3x.html">use_legacy_coding(3x)</A></STRONG> has been called with a  <STRONG>2</STRONG>  parameter,  <STRONG>unctrl</STRONG>
           returns  the  parameter,  i.e.,  a  one-character  string  with the
           parameter as the first  character.   Otherwise,  it  returns  "~@",
           "~A", etc., analogous to "^@", "^A", C0 controls.

           X/Open Curses does not document whether <STRONG>unctrl</STRONG> can be called before
           initializing curses.  This implementation permits that, and returns
           the "~@", etc., values in that case.

       <STRONG>o</STRONG>   parameter values outside the 0 to 255 range.  <STRONG>unctrl</STRONG> returns a null
           pointer.

       The strings returned by <STRONG>unctrl</STRONG> in this implementation are determined at
       compile  time,  showing C1 controls from the upper-128 codes with a "~"
       prefix  rather  than  "^".   Other   implementations   have   different
       conventions.    For  example,  they  may  show  both  sets  of  control
       characters with "^", and strip the parameter to 7 bits.   Or  they  may
       ignore  C1  controls and treat all of the upper-128 codes as printable.
       This implementation uses 8 bits but  does  not  modify  the  string  to
       reflect  locale.   The <STRONG><A HREF="legacy_coding.3x.html">use_legacy_coding(3x)</A></STRONG> function allows the caller
       to change the output of <STRONG>unctrl</STRONG>.

       Likewise, the <STRONG><A HREF="curs_inopts.3x.html">meta(3x)</A></STRONG> function allows the caller to change the  output
       of  <STRONG>keyname</STRONG>,  i.e.,  it  determines  whether to use the "M-" prefix for
       "meta"   keys   (codes   in   the   range   128    to    255).     Both
       <STRONG><A HREF="legacy_coding.3x.html">use_legacy_coding(3x)</A></STRONG>   and  <STRONG><A HREF="curs_inopts.3x.html">meta(3x)</A></STRONG>  succeed  only  after  curses  is
       initialized.  X/Open Curses does not document the  treatment  of  codes
       128 to 159.  When treating them as "meta" keys (or if <STRONG>keyname</STRONG> is called
       before  initializing  curses),  this  implementation  returns   strings
       "M-^@", "M-^A", etc.

       X/Open Curses documents <STRONG>unctrl</STRONG> as declared in <STRONG>&lt;unctrl.h&gt;</STRONG>, which <EM>ncurses</EM>
       does.  However, <EM>ncurses</EM>' <STRONG>&lt;curses.h&gt;</STRONG> includes <STRONG>&lt;unctrl.h&gt;</STRONG>,  matching  the
       behavior of SVr4 curses.  Other implementations may not do that.


</PRE><H3><a name="h3-use_env_use_tioctl">use_env, use_tioctl</a></H3><PRE>
       If  <EM>ncurses</EM>  is  configured  to provide the sp-functions extension, the
       state of <STRONG>use_env</STRONG> and <STRONG>use_tioctl</STRONG> may be  updated  before  creating  each
       <EM>screen</EM>  rather  than  once  only  (<STRONG><A HREF="curs_sp_funcs.3x.html">curs_sp_funcs(3x)</A></STRONG>).  This feature of
       <STRONG>use_env</STRONG> is not provided by other implementations of curses.


</PRE><H2><a name="h2-HISTORY">HISTORY</a></H2><PRE>
       4BSD (1980) introduced <EM>unctrl</EM>, defining it as a macro in <EM>unctrl.h</EM>.

       SVr2 (1984) added <EM>delay</EM><STRONG>_</STRONG><EM>output</EM>, <EM>flushinp</EM>, and <EM>keyname</EM>.

       SVr3 (1987) supplied <EM>filter</EM>.  Later that year,  SVr3.1  brought  <EM>getwin</EM>
       and  <EM>putwin</EM>,  reading  and  writing  window  dumps  with  <STRONG>fread(3)</STRONG>  and
       <STRONG>fwrite(3)</STRONG>, respectively.

       SVr4 (1989) supplied <EM>use</EM><STRONG>_</STRONG><EM>env</EM>.

       X/Open Curses Issue 4 (1995) specified <EM>key</EM><STRONG>_</STRONG><EM>name</EM> and <EM>wunctrl</EM>.

       <EM>ncurses</EM> 5.6 (2006) added <EM>nofilter</EM>, and 6.0 (2015) <EM>use</EM><STRONG>_</STRONG><EM>tioctl</EM>.


</PRE><H2><a name="h2-SEE-ALSO">SEE ALSO</a></H2><PRE>
       <STRONG><A HREF="ncurses.3x.html">curses(3x)</A></STRONG>, <STRONG><A HREF="curs_initscr.3x.html">curs_initscr(3x)</A></STRONG>, <STRONG><A HREF="curs_inopts.3x.html">curs_inopts(3x)</A></STRONG>, <STRONG><A HREF="curs_kernel.3x.html">curs_kernel(3x)</A></STRONG>,
       <STRONG><A HREF="curs_scr_dump.3x.html">curs_scr_dump(3x)</A></STRONG>, <STRONG><A HREF="curs_sp_funcs.3x.html">curs_sp_funcs(3x)</A></STRONG>, <STRONG><A HREF="curs_variables.3x.html">curs_variables(3x)</A></STRONG>,
       <STRONG><A HREF="legacy_coding.3x.html">legacy_coding(3x)</A></STRONG>



ncurses 6.5                       2025-02-15                     <STRONG><A HREF="curs_util.3x.html">curs_util(3x)</A></STRONG>
</PRE>
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<ul>
<li><a href="#h2-NAME">NAME</a></li>
<li><a href="#h2-SYNOPSIS">SYNOPSIS</a></li>
<li><a href="#h2-DESCRIPTION">DESCRIPTION</a>
<ul>
<li><a href="#h3-unctrl_wunctrl">unctrl, wunctrl</a></li>
<li><a href="#h3-keyname_key_name">keyname, key_name</a></li>
<li><a href="#h3-filter_nofilter">filter, nofilter</a></li>
<li><a href="#h3-use_env">use_env</a></li>
<li><a href="#h3-use_tioctl">use_tioctl</a></li>
<li><a href="#h3-putwin_getwin">putwin, getwin</a></li>
<li><a href="#h3-delay_output">delay_output</a></li>
<li><a href="#h3-flushinp">flushinp</a></li>
</ul>
</li>
<li><a href="#h2-RETURN-VALUE">RETURN VALUE</a></li>
<li><a href="#h2-NOTES">NOTES</a></li>
<li><a href="#h2-PORTABILITY">PORTABILITY</a>
<ul>
<li><a href="#h3-filter">filter</a></li>
<li><a href="#h3-delay_output-padding">delay_output padding</a></li>
<li><a href="#h3-keyname">keyname</a></li>
<li><a href="#h3-nofilter_use_tioctl">nofilter, use_tioctl</a></li>
<li><a href="#h3-putwin_getwin-file-format">putwin/getwin file-format</a></li>
<li><a href="#h3-unctrl_wunctrl">unctrl, wunctrl</a></li>
<li><a href="#h3-use_env_use_tioctl">use_env, use_tioctl</a></li>
</ul>
</li>
<li><a href="#h2-HISTORY">HISTORY</a></li>
<li><a href="#h2-SEE-ALSO">SEE ALSO</a></li>
</ul>
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